1. Field of the Invention
The present invention relates generally to fluid flow connector devices of the type used for interconnecting two flexible pipes carrying a fluid and more specifically, to an improved threaded fluid flow connector wherein the nipple and coupler thereof are interconnected by a threaded engagement.
2. Prior Art
Fluid flow connector which comprise mating coupler and nipple portions, are commonly used on interconnectable, flexible pipes or hoses for transferring a fluid therebetween. Fluid flow connector generally enable expedient connection and separation of such hoses or pipes wherein the flow path is automatically interrupted upon separation to prevent the leakage of any substantial amount of fluid and is automatically unblocked or uninterrupted upon interconnection of the coupler and nipple to enable free flow of fluids therebetween upon connection. Once the coupler and nipple of a fluid flow connector have been interconnected, there are a variety of ways to secure them to one another so that they cannot inadvertently become separated and interrupt the flow of fluid therebetween when unattended. One of the most secure ways of interconnecting the nipple and coupler of a fluid flow connector is by threaded engagement therebetween.
The present invention comprises a threaded fluid flow connector in which the novel features may be identified as a means for limiting the locking torque between the coupler and nipple and a positive pull-slide action requirement for beginning the unthreading or decoupling of the nipple and coupler in order to prevent inadvertent decoupling. The most relevant prior art in regard to these features of the threaded fluid flow connector of the present invention and which are known to the applicant include the following:
U.S. Pat. No. 1,477,440 Grief, Jr. PA1 U.S. Pat. No. 1,866,863 Richardson PA1 U.S. Pat. No. 3,100,655 Work PA1 U.S. Pat. No. 3,519,975 Prow, Jr. et al PA1 U.S. Pat. No. 3,524,160 Robinson PA1 U.S. Pat. No. 3,656,781 Paine et al PA1 U.S. Pat. No. 3,727,952 Richardson PA1 U.S. Pat. No. 3,888,559 Geib PA1 U.S. Pat. No. 4,005,735 Miyamoto
U.S. Pat. No. 4,005,735 to Miyamoto shows an adaptor with a thread protector and the end of the adaptor is threadedly engaged on the hose ferrule. A sleeve is biased forwardly by a spring so that a member extends over and protectively encloses the male threads. When the device is to be connected to something like a nozzle, the sleeve is moved axially away from the threads which exposes them and the nozzle is attached.
U.S. Pat. No. 3,888,559 to Geib is directed to a high voltage fluid flow connector assembly. A locking cylinder includes a sleeve portion which surrounds a portion of a shell near the base portion. The sleeve portion ends at an end surface which abuts the shoulder portion formed around the periphery of the base portion. Thus, the locking cylinder may only be moved toward the base portion until the end surface of the sleeve portion engages the shoulder of the base. A coil spring is positioned between the outer surface of the cylindrical shell and the sleeve portion of the locking cylinder. An end of the coil spring abuts the shoulder coupled to the cylindrical shell while the other end of the coil spring abuts a shoulder which forms a portion of the cylinder. In this manner, the spring biases the locking cylinder away from the base portion.
U.S. Pat. No. 3,727,952 to Richardson is directed to a tube connector system where a sleeve may be retracted and which opens collets which allows for the placement of the connector over a fitting of the equipment.
U.S. Pat. No. 1,866,863 to Richardson is directed to a drill steel retainer and although it works on a somewhat different principle, to remove a sleeve to place the drill, a collar is pressed in a backward direction against the pressure of a spring to disengage lugs of the collar from recesses of the sleeve. The sleeve is then rotated to move the lugs from the grooves and the sleeve is slid off the head.
Based upon the above, it is readily apparent that there are no known prior art U.S. patents which disclose a threaded fluid flow connector in which there are means for limiting the threading torque to avoid inadvertent over-threading and subsequent damage to the interconnecting parts of the fluid flow connector, nor is there any prior art U.S. patents which disclose a means for requiring a positive, manual, springbiased, pull-slide action for unthreading the coupler and nipple of a threaded fluid flow connector in order to avoid inadvertent decoupling.